Closed tube with fastener members



April 30, 1968 0. K. KRAUS CLOSED TUBE WITH FASTENER MEMBERS 3Sheets-Sheet 1 Filed March 2. 1962 INVENTOR Oifa har/ Kraus BY Z1 44 QApril 30, 1968 0-K. KRAUS 3,380,481

CLOSED TUBE WITH FASTENER MEMBERS Filed March 2, 1962 3 Sheets-SheetINVENTOR. 0X50 Kar/ A ra us April 30, 1968 0. K. KYRAUS 3,380,481

CLOSED TUBE WITH FASTENER MEMBERS Filed March 2. 1962 3 Sheets-Sheet 3INVENTOR. 0/50 Ker/K7454;

United States Patent 3,330,481 CLOSED TUBE WITH FASTENER MEMBERS OttoKarl Kraus, Rego Park, N.Y., ass-R noir, by inesne assignments, toMinigrip, Inc., New York, N.Y., a corporation of New York Filed Mar. 2,1962, Ser. No. 176,926 4 Claims. (Cl. 138-118) ABSTRACT OF THEDISCLOSURE An elongated flexible closed one-piece tube having integrallyformed longitudinally continuous interlocking elements formed thereonfor slitting, cutting and sealing to form closeahle and reusable pouchesor bags therefrom.

The present invention relates to an improved pouch having a flexibleclosure and method of making the pouch, and more particularly to a tubeand method of making a continuous tube which can be converted into areusable air tight and water tight pouch with reclosable closureelements thereon.

The present invention contemplates the manufacture of a flexible bag orpouch by the formation of a closure including an elongated flexibleclosed one piece integral tube. The tube is formed by extruding througha single annular die opening and has continuous interlocking elementsextended axially along the tube at circumferentially spaced locations,which are extruded simultaneously therewith and integral with thematerial of the tube.

The tube profiles are then joined and the tube is then separated or slitlongitudinally between the interlocking elements in one or more placesto form one or more continuous strips that can then be made intodifferent types of bags or pouches,

An important advantage of the tube is the ease in which it can be turnedinto a reusable air tight and water tight pouch. Pouches heretofore havebeen made by much longer and more expensive processes, e.g. the closurestrips or zipper for closing the pouch has been made in one extrusionprocess and the film for the bag by another process. The Zipper and filmare then combined by a process requiring two or three different steps.

Accordingly it is an object of the present invention to provide animproved method for forming flexible closure strips and bag walls andstructure for providing the strips and walls wherein the strips andwalls can be extruded as a single integral unit and extrusion can beaccomplished through a single annular die opening avoiding disadvantagesof extrusion and sealing processes and dies of the type heretofore used.

Another object of this invention is the provision of a method of makinga unitary closed tube with fastener profiles thereon which can bepositioned at different locations on the tube for forming bags whereinthe side walls of the bag and the fastener strips are integral.

A further object of the invention is the provision of a continuousintegral tube with a series of integral interengageable profiles, whichwhen joined, and the tube cut and processed, make possible themanufacture of air tight and water tight reusable containers in a muchmore economical and rapid method than heretofore.

A general object of the invention is to provide an improved structureand method of forming material for bags with closures which effect asaving in time and cost of manufacture over structures and methodsheretofore available.

Other objects, advantages and features will become more apparent withthe teaching of the principles of the invention in connection with thedisclosure of the preferred embodiments thereof in the specification,claims and drawings, in which:

FIGURE 1 is a perspective view with a vertical section takentherethrough of a bag utilizing a tube with integral closure strips ofthe type embodied in the present invention;

FIGURE 2 is an elevational view shown in somewhat schematic form of adie with a tube being extruded therefrom;

FIGURE 3 is an end elevational view shown in somewhat schematic form ofa tube constructed in accordance with the principles of the presentinvention;

FIGURE 4 is also an end elevational view showing a tube of modifiedconstruction;

FIGURES 5 through 8 are fragmentary end elevational views shown insomewhat schematic form of arrangements of closure elements on tubes;

FIGURE 9 is a fragmentary perspective view illustrating separating thematerial of the tube to form separate strips;

FIGURES 10 through 14 are fragmentary perspective views illustratingways of cutting tubes having the structure of the present invention;

FIGURE 15 is a fragmentary perspective view showing a tube withperforations situated in the wall;

FIGURE 16 is a fragmentary perspective view illustrating a manner ofseparating the tube of FIGURE 15;

FIGURE 17 is a fragmentary perspective view showing the formation ofopenings in the tube wall;

FIGURE 18 is a fragmentary perspective view showing another step inpreparing a tubesuch as shown in FIGURE 17;

FIGURE 19 is a fragmentary perspective view showing a tube with areinforced wall portion;

FIGURE 20 is a fragmentary perspective view showing a tube with a gussetfold; and

FIGURE 21 is a schematic perspective view showing another arrangement oftube structure.

As shown on the drawings:

FIGURE 1 illustrates a pouch or bag 10 having side walls 11 and 12arranged to form a container and being integral with each other. Theirside edges are closed by seams 13 to complete the container, and the topis closed by a flexible closure structure provided by first and secondclosure strips 14 and 15. The closure strips are situated at the top ofthe bag It} and are integral with the bag walls. Flanges 2t and 21 areintegrally attached to the strips to extend upwardly therefrom, and arean integral part of the container, and are extruded with the containerand strips, being joined when extruded, and later cut during processing.In all arrangements the closure strips are integral with the bag walls11 and 12 and formed of the same material.

On the inner facing surfaces the closure strips are provided withinterlocking elements shown in the form of longitudinally extending ribs16 and grooves 17. These ribs and grooves are approximatelycomplementary shaped so that the ribs will press into the grooves when aclosing pressure is applied to the outer surfaces of the strips 14 and15. Similarly the ribs will be pulled out of the grooves when the stripsare forcibly pulled apart such as by gripping the upstanding flanges 20and 21 on the strips.

It will be understood that the invention embodies use of various typesof interlocking members of the type which lock when they are pressedtogether and separate when forcibly pulled apart, such as illustratedfor example in the Madsen Patents 2,558,367 and 2,637,085. Closure andseparation of the strips may be accomplished manually such as bypressing the strips together between the thumb and forefinger, anddrawing them apart with the hands.

The closure strips are made of a resilient plastic material and areconveniently manufactured by being extruded from a die along with thetube to which they are integral ly attached. Thermoplastic andthermosetting organic synthetic resins are suitable for use, and ofparticular importance for this use are the vinyl type resins such aspolyvinyl chloride, polyvinyl acetate, polyvinyl chloridepolyvinylacetate copolymers, and similar vinyl resins, and polyethylene. Rubber,either natural or synthetic, is not a preferred material since, in thecase of rubber, it is more difficult to control the degree of rigidityfor interlocking engagement between the strips. However, by propercompounding and vulcanizing the rubber, the degree of rigidity can becontrolled to make rubber acceptable for purposes of the instantinvention.

In accordance with the principles of the invention, such as illustratedin FIGURE 2, an elongated flexible closed integral annular tube 22 isprovided with interlocking elements 23 and 24 formed integrally on thesurface of the tube and extending axially therealong. As previouslystated the interlocking elements may be of different shapes andconfigurations, and for convenience of illustration are shown as beingsingle elements, and the elements generally will be characterized byproviding a rib with overhanging shoulders or locking surfaces 25 whichare receivable in a mating co-acting groove 26.

In accordance with the method of the invention the tube 22 is extrudedthrough a die 27 having an annular continuous opening 28. Theinterlocking elements 23 and 24 are simultaneously extruded so as to beintegral with the tube, through projecting conformations in die opening28. Plastic is supplied to the die from a plastic feeder 29 whichincorporates suitable plastic feeding and supply mechanism which neednot be described in detail as will be appreciated by those versed in theart.

FIGURE 2 illustrates the interlocking elements 23 and 24 as being formedon the outer surface of the tube 22, and the elements in question canalso be formed on the inner surface.

While the tubes of the different figures are shown as being of differentdiameters, it will be understood that a diameter is chosen in accordancewith the size of bag that is required, and the sizes shown are chosenfor convenience of illustration.

'In the arrangement of FIGURE 3, a tube 29 is formed with one of theinterlocking elements 60 on the inner surface of the tube and the otherinterlocking element 31 on the outer surface. This arrangement will beadvantageous in certain environments depending upon the use to which thestrips are to be put, and depending upon the handling methods andmechanism for cutting .the tube, as will be discussed. The tube 29 isshown with the male interlocking element on the inner surface of thetube and the female element 31 on the outer surface, but it will beunderstood that these positions may be interchanged.

FIGURE 4 illustrates a tube with plural sets of interlocking elements onthe surface, with the sets shown on the inner surface. A tube 32 isshown formed in the same manner as the tube in FIGURE 2, and has a maleinterlocking element 33 and a female element 34 adjacent each other onthe inner surface, and also has a male element 35 and a female element36 adjacent each other at the other side of the inner surface of thetube. The elements have complementary shapes so that either of thefemale elements may be used :with either of the male elements to providefor variations in cutting the tube longitudinally.

In FIGURE a tube 37 is formed with interlocking elements on its innersurface, with female elements 38 and '39 at one side of the tube, andmale elements 40 and 41 at the other side of the tube. The elementsdescribed above could also be formed on the outer surfaces of the tube.

FIGURE 6 illustrates a tube 42 with elements provided on the outside orouter surface of the tube, with a male element 43 and a female element44 on one side, and with a female element 45 and a male element 46 atthe other side of the tube, diametrically opposite the first set ofelements 43 and 44. In some instances the positions of either of theelements may be interchanged, that is, the locations of the elements 43and 44 may be changed.

FIGURE 7 illustrates a tube 47 with multiple profiles or interlockingelements arranged on the inside and outside of the tube, with maleelements 48 and 49 within the tube opposite each other, and femaleelements 50 and 51 outside of the tube opposite each other. In someinstances it may be desired to reverse the locations of each of the maleand female elements, that is, the positions of elements 48 and 50 couldbe interchanged, and the positions of elements 49 and 51 could beinterchanged.

FIGURE 8 illustrates a tube 52 wherein the interlocking element-s orprofiles are arranged so that the female and male elements are onopposite sides of the tube surfaces, and the male elements 53 and 54 areside-byside on one side of the tube within the inner surface, and thefemale elements 55 and 56 are side-by-side on the outer surface of thetube, positioned substantially diametrically opposite the male elements.Again, the positions of both female elements can be interchanged withthe positions of both male elements.

As will be appreciated from the descriptions and illustrations of theforegoing figures, the structure incorporates an elongated flexibleclosed integral tube with axially extending interlocking elements orprofiles on the surface thereof, with the positions of the profileschangeable to accomplish the different desired results.

FIGURE 9 illustrates a closed integral tube 57 with interlocking profileelements 58 and 59 thereon. To prepare the structure for use as a flatstrip with male and female elements near the edges, a knife 60 is usedto slit the tube in a longitudinal or axial direction forming a severingline 61. The severed strip which will result will have edges withprofiles thereon, and it will be observed that this will form a flatstrip for attachment to other strips, or can be doubled for use as a bagwith the elements 58 and 59 brought together in interlocked face-tofacerelationship. For use as a bag, the diameter of the tube can be mademuch larger to provide adequate material for the bag walls. Separatebags may be formed along the length of the continuous tube by bringingthe material radially together and forming flat seams to completeindividual containers having the general appearance of the container ofFIGURE 1, with a base of the bag being formed by the double layer ofmaterial, unless provision is made for a bottom open bag. The side seams13 may be formed by various methods, such as by heat sealing the layerstogether and cutting the bag from the supply length, such as by applyinga heated cutting and sealing wire if a thermoplastic material is used.

FIGURE 10 illustrates a method of severing a closed integral tube 62with interlocking profile elements 63 and 64 on the inner surface. Aknife 65 forms a severed line 66 extending axially between the elements63 and 64. Another cut is formed by a knife 67 along a severance line 68opposite the first severance line 66, and this will result in separatefastener strips with the interlocking elements 63 and 64 at their upperedges. When the interlocking elements of these strips are joined andafter the side seams have been made, the result will be a bottom openbag for bottom loading.

FIGURE 11 illustrates another method of severing tubes such as thoseillustrated in FIGURES 9 and 10. A tube 69 has interlocking elements 70and 71 on the inner surface, and is severed longitudinally along theline 72 by a knife 73. The position of the severance line 72 is suchthat it is closer to one of the interlocking elements than to the other.In other words, the distance shown at 74 is less than the distance shownat 75, and this will result in the flange 76 being longer than theflange 77 which will afford convenience in separating the stripsmanually.

FIGURE 12 shows the method of forming separate strips from a tube 78having male and female interlocking elements 79 and 80 on the innersurface at one side of the tube and similar female and male elements 81and 82 at the other side of the tube. A cut 83 is made by a knife 84between the elements 81 and 82, and a similar cut 86 is made by a knife85 between the other elements. This forms two separate strips 87 and 88,each with a male and female element at their side edges, and as will beseen from the showing of FIGURE 12 this arrangement could be used toform two rows of pouches in a manufacturing operation.

FIGURE 13 shows a method of severing a closed integral tube 89 havingmale and female elements 90 .and 91 on the inner surface at one side,and female and male elements 92 and 93 on the inner surface opposite thefirst pair of elements. Severances are made between each pair ofelements along a line 95 by a knife 94, and along a line 97 by a knife96. Additional cuts are made between the male and female elements 90 and92 by a knife 98, and between the elements 91 and 93 by a knife 99,thereby providing four separate closure strips 100, 101, 102 and 103,each of which has a closure element at its edge. This arrangement couldbe used to form two rows of bottom open pouches in a manufacturingoperation.

FIGURE 14 illustrates a method of severing a closed integral tube 104 ina manner similar to that previously described, but where the tube hasadjacent male elements 105 and 108, and adjacent female elements 106 and107. The tube is severed by a longitudinal severance line 111 betweenthe female elements by a knife 112, and between the male elements alonga longitudinal severance line 109 by a knife 110, thereby providingstrips with male and female elements at their respective edges.

FIGURE 15 illustrates a tube 113 with interlocking elements 114 and 115and a severance line 116 therebetween. The severance line is providedfor manual separation by perforations or cut slots such as may be formedby a perforating wheel 117. This eventually provides a pouch whosefastener elements when engaged cannot be separated until the perforationis torn.

FIGURE 16 illustrates a tube 118 with a pair of interlocking elements119 at one side of the tube on the inner surface, and another pair ofelements 120 within the tube at the other side. Between the elements ofthe pair 119 and of the pair 120 are rows of perforations 122a and 122b.The tube is separated by knives 123 and 124 which form longitudinal cutsbetween the pairs, thus providing two separated continuous strips whichcan be further separated by tearing the perforations 122a and 122b, or

for eventually creating two sets of bottom open perforated pouches.

FIGURE 17 illustrates a closed tube 125 with an interengaging pair ofinterlocking elements 126 and 127 on the inner surface. In a parallelline at separated intervals are provided holes 128 and 129 adjacent andbetween the elements 126 and 127. The holes may be made in a suitablemanner such as by punches 130 and 131. The tube is severed by a cut 133formed by .a knife 132. The holes 128 and 129 will provide means forreceiving a hook such as that provided on a peg board. If a tube iseventually made into bags, each of the bags will have a series of holesalong its top for conveniently suspending or hanging the bag.

FIGURE 18 illustrates a combination of the previous features, with atube 134 having interlocking elements 135 thereon, and rows of holes 136provided by punches 137, between the elements. Between the holes is arow of weakening perforations 138 provided by a perforating wheel 139,and thus the completed tube provides a unit which can be easilyseparated at the weakened points and for providing bags which will haveholes along their tops.

FIGURE 19 illustrates a continuous closed tube 140 with interlockingelements 141 and 142 wherein the wall of the tube is thicker at onecircumferential location than another. This can easily be controlled bythe size of the opening in the extruding die. The tube has a thickenedportion 143 provided in the tube wall between the interlocking elements141 and 142. Holes 146 and 1147 which are longitudinally spaced extendthrough the thickened portion and are arranged in rows, and a cut 144 isformed by a knife 145 between the rows of holes. In this illustrationthe thickened portion is used for strengthening the material around theholes. It will be understood that the invention contemplates thickeningthe Wall structure of the tube at any location where such thickening isnecessary to perform a particular function such as strengthening a pointof weakness or for serving a particular purpose for which the strips orthe eventual container is designed. For example, if the tube were usedto form a series of bags, it may be desirable to have a thickenedportion along the base of the bag where the greatest amount of wear andscuff, and where a fold occurs.

FIGURE 20 illustrates a tube 148 with a pair of interlocking elements149 in the inner surface. The tube is of a size to form a completed bag,and has an inwardly folded gusset 150 along one side at a location whichwill form the base of the bag. When a slit is formed by a knife 151between the interlocking elements 149, the bag will be ready to beformed, and a bag with a base gusset will result. As will beappreciated, if the tube is made of a thermoplastic material, lengthscan be severed therefrom, and the bags completed by applying a heatedmember such as a wire across the bag to simultaneously cut this bag fromthe supply length and form the seam.

Thus it will be seen that I have provided a closure structure and amethod of forming of the structure which meets the objectives andadvantages above set forth. The structure provides a joined tube onwhich has been extruded one or more profiles. Substantial advantages areachieved in the extrusion process of extruding a continuous enclosedtube as opposed to a strip, and the method and structure have a widerange of adaptability.

The drawings and specification present a detailed disclosure of thepreferred embodiments of the invention, and it is to be understood thatthe invention is not limited to the specific forms disclosed, but coversall modifications, changes, alternative constructions, combinations ofdifferent disclosures herein and methods falling within the scope of theprinciples taught by the invention.

In the arrangements of FIGURES 15 and 16, double rows of perforationsmay be provided. Then when the material is folded and the fastenerelements interlocked, a double strip will be formed at the bag top whichcan be torn off. The area between the perforations may be coloreddifferently than the rest of the material for easily distinguishing thetop double strip.

In the arrangement of FIGURE 21, an elongated continuous flexibleplastic tube 152 has fastener profiles 153 and 154 extending therealongfor forming closure elements. To separate the tube and form flanges atthe top of the bag which is to be constructed, a knife blade 156 is runalong between the fastener elements 153 and 154 along a line ofseverance 157. The tube is provided with an integral colored linelocated between the male and female profiles 153 and 154. The coloredline will be extruded simultaneously with the tube. With the line ofseverance 157 formed in the middle of the line, the opening flanges willeach be marked with a colored outer edge. If desired, the colored line155 and the line of severance 157 can be related so that the cut isalong the edge of the colored line 155, and then only one of the flangeswill be colored for ease of separation. It will be understood that anyof the structures of FIGURES 2 through 20 may be provided with a coloredline or colored lines between the male and female interlocking profilesand the tubes cut axially along the center of the colored line or lines,or along the edge or edges thereof.

I claim as my invention:

1. A structure for use in making a reclosable container comprising,

an elongated closed flexible integral tube, a first interlocking elementintegral with the tube on the inner surface thereof, and a secondinterlocking element integral with the tube on the outer surfacethereof,

said elements being shaped for cooperative pressure interengagement andforcible separation.

2. The structure as defined in claim 1 and including means defining aseparational line extending longitudinally along the tube for separatingthe tube material between said interlocking elements.

3. The structure as defined in claim 1, said tube having longitudinallyspaced holes positioned between the interlocking elements.

4. The structure as defined in claim 1 wherein one of said interlockingelements comprises a rib having overhanging shoulders and the other ofsaid elements comprises means forming a complementarily shaped groovefor receiving said rib.

References Cited UNITED STATES PATENTS 3,198,228 8/1965 Naito 15692 X3,246,672 4/1966 Naito 138118 3,291,177 12/1966 Naito 150-3 2,666,4661/1954 Sharat 15692 3,038,217 6/1962 Harris 156244 2,558,367 6/1951Madsen 15692 2,637,085 5/1953 Madsen 15692 X 2,791,807 5/1957 Morin15443 2,144,755 1/1939 Freedman 15692 EARL M. BERGERT, Primary Examiner.

H. F. EPSTEIN, Assistant Examiner.

